Shanghai, London: Rafael Nadal made light work of the unseeded American Jared Donaldson to sprint into the third round of the Shanghai Masters on Wednesday.

The world No. 1, fresh from winning the China Open and the US Open, ruthlessly disposed of the world-ranked 56 Donaldson, 6-2, 6-1 in just 54 minutes. Nadal, a 16-time Grand Slam winner, plays Italian Fabio Fognini in the next round.

Australia’s Nick Kyrgios has been fined $10,000 and deducted his $21,000 first-round losers’ cheque following his decision to walk off after losing the first set against Steve Johnson on Tuesday.

The tempestuous Kyrgios had just been beaten in a tiebreak against Johnson when he walked to the net, offered his hand to the American and stormed off court to the bemusement of his opponent and chair umpire Fergus Murphy.

Kyrgios, 22, was booed off court by the crowd.

The ATP said on Wednesday that Kyrgios had been punished for “unsportsmanlike conduct”, saying he had failed to complete a medical visit to explain his actions.

Kyrgios, ranked 21 in the world, said later on Twitter that he had been suffering with a stomach bug and a shoulder problem.

“I’ve been battling a stomach bug for the past 24 hours and I tried to be ready, but I was really struggling on the court today, which I think was pretty evident from the first point,” Kyrgios said.

“My shoulder started to hurt in the practice, which didn’t help either and once I lost the first set I was just not strong enough to continue. I’ve not eaten much in the past 24 hours.”

Last year, Kyrgios was fined $16,500 and banned for eight weeks for deliberately throwing a game during his second-round defeat by Mischa Zverev in Shanghai.

In Hong Kong Open, Japanese teenager Naomi Osaka fought back from an early break to stun Venus Williams in straight sets and move through to the quarter-finals.

Osaka, who prevailed 7-5, 6-2 for her best career win by ranking, double-faulted early in the opening set to hand seven-time grand slam champion Williams the advantage.

The 19-year-old broke back and levelled at 5-5 as the world No. 5 looked to serve for a 1-0 lead. Osaka then pounced on Venus’ serve to break again and took the first set.

“I feel like even if I hit one semi-short ball she would come in and crush it, so I had to play really well,” Osaka said after the match.

Ranked 64 in the world, Osaka began to dictate terms in the second set, racing to 5-0. Venus held her serve to avoid the humiliation of a bagel and broke Osaka to make it 5-2.

A double fault by the 37-year-old handed Osaka two match points and the youngster took the first in style to gain revenge for her loss to the American in the third round at Wimbledon.